After what we can all agree was a rather rollercoaster-y and rushed romance between Kate and Toby for much of season 1 of This Is Us, the engaged couple wisely decided to take a deep breath instead of racing to the altar. When we last saw the pair in the season 1 finale of the NBC family drama, Kate (Chrissy Metz) and Toby (Chris Sullivan) were unpacking literally and figuratively as they moved in together.

So, guess they’ll live happily and undramatically ever after, yes? Well, let’s not write the end of this fairy tale with a quill pen just yet. “A lot of people aren’t necessarily friends after they’ve moved in with each other, and it’s really, really hard,” hints Metz. “I’m not foreshadowing anything with Toby and Kate, but he’s put her first and she’s learning to put herself first.”

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Indeed, while Kate pursues a singing career, following in the footsteps of her mother, Rebecca (Mandy Moore), “they’re definitely learning the dynamics of cohabiting with another human being,” says Metz. “They had a lot going on in the first year of their relationship, you know? But I think they truly do love each other and they get each other and they’re there to support one another through all of the highs and lows. But there are definitely going to be some lows. And just like life continues to throw curveballs, we’ll see some of those early on in the season.”

“Do you think anybody on This Is Us is going to have an easy ride?” says Sullivan with a laugh, adding: “They’re trying to figure out what the next steps are. They’re getting down to brass tacks. They’re getting around all of the superficial flirting and infatuation and getting real and getting honest — and facing a lot of the things that scare them.”

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King of the grand gestures, Toby had a huge scare last season — see the Christmas collapse — and almost wound up in an urn like Jack (Milo Ventimiglia), but he seemed to weather the medical storm. “There are often two strong reactions to adversity or to extreme pain in people’s life,” says Sullivan. “I know people who have had near-death experiences or who have experienced terminal illness and come through the other side. There are people who react to that experience with eternal hope and lightness, and there are people who have a reaction where that experience takes all of the light out of everything, and I think Toby is in the former. And these experiences have given him a positive bent on most things. That state of mind doesn’t always win out, but he gives it his best.”

Will the couple overcome their fears, insecurities, and challenges in a way that viewers should plan on a wedding later in this season? “We’ll see if they’re able to,” says Sullivan. “I don’t know if you’ve ever planned a wedding, but it’s super hard to do in 18 episodes. That’s not enough time to plan a wedding. We’ll see if they get there.”

All of that may — or may not — depend on one sentence that Metz drops when discussing Kate’s trajectory this season: “There are some unforeseen twists that I had no idea were coming.”

For a preview of what to expect in the season premiere — including the “huge puzzle piece” about Jack’s death — head here.